|
-
POSTING RULES

-
Donate yearly (please).
-
Advertise in here!
-
Today's Posts
|
Insert Pics
|

05-02-2017, 08:05 PM
|
|
|
|
Join Date: Mar 2008
Location: Dublin, CA
Posts: 1,261
|
|
Lots of stories on VAF about failed alternators. Batteries are a maintanence item that can have a low probability of failure if properly maintained. I plan a dual alternator system. I may have a small secondary battery too but my first line of defense is the backup alternator.
__________________
Ray Tonks
2020 Donation Paid
Titan IOX-370, Dual PMAGs, 9.6:1 Pistons, FM-150
RV-7 Fuselage in progress
* Cabin Interior - In progress
RV-7 SB Wings
* Both Wings fully skinned
* Fuel Tanks Complete - No leaks finally
* Ailerons Complete
* Flaps Complete
RV-7 Empennage - Complete (a little fiberglass work left)
Vans Training Kit # 2 - Complete
RV-7 Preview Plans
Vans Training Kit #1 - Complete
EAA Sheet Metal Class - Complete
|

05-02-2017, 08:43 PM
|
|
|
|
Join Date: Sep 2007
Location: BC
Posts: 1,674
|
|
Batteries degrade (fail) slowly over time in that they store less useable energy, and yet we still fly with them never really knowing their capacity at that particular time.
__________________
RV7A Flying since 2015
O-360-A1F6 (parallel valve) 180HP
Dual P-mags
Precision F.I. with AP purge valve
Vinyl Wrapped Exterior
Grand Rapids EFIS
Located in western Canada
|

05-02-2017, 09:34 PM
|
 |
|
|
Join Date: Sep 2005
Location: Maple Grove, MN
Posts: 2,333
|
|
two alternators vs two batteries
It also depends also on the type of ignition one has. I have dual lightspeed ignitions, so I prefer two batteries. I have a setup to test the backup battery (whose only function is to feed the second ignition) using a 12v lamp. This draws a known current, so I can calculate the effective amp-hrs available until it drops to some specific voltage. I test it annually.
__________________
Alex Peterson
RV6A N66AP 1700+ hours
KADC, Wadena, MN
|

05-03-2017, 05:26 AM
|
 |
|
|
Join Date: Oct 2005
Location: 08A
Posts: 9,500
|
|
There is no one answer.
I entirely agree with the dual alternator strategy for an IFR bird, and lean toward dual alt/dual battery for EFI/EI.
That said, the KIS approach to VFR with a low-draw (<1 amp) electronic ignition is a small secondary battery. KIS is good.
__________________
Dan Horton
RV-8 SS
Barrett IO-390
|

05-03-2017, 05:37 AM
|
|
Super Moderator
|
|
Join Date: May 2005
Location: Locust Grove, GA
Posts: 2,626
|
|
Quote:
Originally Posted by AlexPeterson
It also depends also on the type of ignition one has. I have dual lightspeed ignitions, so I prefer two batteries. I have a setup to test the backup battery (whose only function is to feed the second ignition) using a 12v lamp. This draws a known current, so I can calculate the effective amp-hrs available until it drops to some specific voltage. I test it annually.
|
For those with dual electronic ignitions I would encourage you to check the backup battery as often as possible, certainly more than once per year. I have seen more than one airplane come through my shop with the backup battery reading 5 volts! Sometimes it was due to a charging system failure and sometimes it was a corroded connector on the battery. Klaus has a schematic that allows you to test the backup battery prior to takeoff.
Vic
__________________
 Vic Syracuse
Built RV-4, RV-6, 2-RV-10's, RV-7A, RV-8, Prescott Pusher, Kitfox Model II, Kitfox Speedster, Kitfox 7 Super Sport, Just Superstol, DAR, A&P/IA, EAA Tech Counselor/Flight Advisor, CFII-ASMEL/ASES
Kitplanes "Unairworthy" monthly feature
EAA Sport Aviation "Checkpoints" column
EAA Homebuilt Council Chair/member EAA BOD
Author "Pre-Buy Guide for Amateur-Built Aircraft"
www.Baselegaviation.com
|

05-03-2017, 07:10 AM
|
 |
|
|
Join Date: Sep 2005
Location: Maple Grove, MN
Posts: 2,333
|
|
Quote:
Originally Posted by vic syracuse
For those with dual electronic ignitions I would encourage you to check the backup battery as often as possible, certainly more than once per year. I have seen more than one airplane come through my shop with the backup battery reading 5 volts! Sometimes it was due to a charging system failure and sometimes it was a corroded connector on the battery. Klaus has a schematic that allows you to test the backup battery prior to takeoff.
Vic
|
Good point - I do check the voltage of this battery prior to startup before every flight. I also full time monitor its voltage during flight to be sure the proper charging voltage is being applied. The test I do annually is a capacity check, where I run it down to perhaps 10 volts, to determine amp-hr capacity.
__________________
Alex Peterson
RV6A N66AP 1700+ hours
KADC, Wadena, MN
|

05-03-2017, 07:16 AM
|
 |
|
|
Join Date: Oct 2008
Location: Hales Corners, WI
Posts: 981
|
|
You should check with Rosie about this, but read his Carribean trip thread first! 
__________________
Jesse Bentley
N229Z - RV-8 - Flying - Livin' the dream!
|

05-03-2017, 10:19 AM
|
|
|
|
Join Date: Dec 2012
Location: Carrollton, GA 5GA2
Posts: 259
|
|
Thank you all for the replies
I feel like the available backup-battery solutions are getting better but maybe not the ideal situation for me just yet. And the points about how to avoid getting stranded somewhere are well made. While my mission won't take me into austere locations we have all seen how deserted ramps are late on a weekend evening when we're trying to get home.
I will be talking with Stein very soon and I'm sure he will provide some great options to consider. Thanks for the input - it is always valuable and always appreciated.
__________________
James Hartline
Carrollton, GA 5GA2
RV-14 - First flight 4/7/2019. Phase I complete as of 9/11/2019!!
|

05-03-2017, 11:43 AM
|
|
Super Moderator
|
|
Join Date: May 2005
Location: Locust Grove, GA
Posts: 2,626
|
|
Well done
Quote:
Originally Posted by AlexPeterson
Good point - I do check the voltage of this battery prior to startup before every flight. I also full time monitor its voltage during flight to be sure the proper charging voltage is being applied. The test I do annually is a capacity check, where I run it down to perhaps 10 volts, to determine amp-hr capacity.
|
Well done!
Vic
__________________
 Vic Syracuse
Built RV-4, RV-6, 2-RV-10's, RV-7A, RV-8, Prescott Pusher, Kitfox Model II, Kitfox Speedster, Kitfox 7 Super Sport, Just Superstol, DAR, A&P/IA, EAA Tech Counselor/Flight Advisor, CFII-ASMEL/ASES
Kitplanes "Unairworthy" monthly feature
EAA Sport Aviation "Checkpoints" column
EAA Homebuilt Council Chair/member EAA BOD
Author "Pre-Buy Guide for Amateur-Built Aircraft"
www.Baselegaviation.com
|
Posting Rules
|
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts
HTML code is Off
|
|
|
All times are GMT -6. The time now is 01:54 AM.
|